Cutter chain for mining machines



Oct. 30 1923. 1,472,736

T. E. PRAY CUTTER CHAIN FOR MINING MACHINES Filed Dec. 16 1920 Patented Oct. 30, 1923.

UMTED STATES PATENT ormcno;

THOMAS E. PRAY, OF CHICAGO, ILLINOIS, ASSIGNOR TO GOODMAN MANUFACTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

' CUTTER CHAIN FOR MINING Ill/IAGI-IINES.

Application filed December 16, 1920. Serial No. 431,250.

To all wkom'z't may concern:

Be it known that I, TjioMAs E. PRAY, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a Cutter Chain for Mining Machines, of which the following is a specification.

This invention relates to improvements in cutter chains for mining machines, and has for its principal object'to provide a simple and durable construction of chain block and cutter bit. v

The invention may best be understood by reference to the accompanying drawings,

in which- Figure 1 is a side view of the chain block with the bit in place therein.

Figure 2 is an end View of the chain showing it in position in a cutter head of a min in% machine.

igure 3 is a sectional View taken on line 3-3 of Figure 1.

Figure 4 is a perspective view of the chain block. 7 I v Like numerals refer to like parts throughout the several figures.

In the drawings, I have shown a cutter chain for mining machines. This chain is made up of a series of chain blocks 1, 1, e pivotally connected together by-a series of straps 2, 2. The chain in use is anendless chain and passes about a sprocket and work in a groove. This groove is provided at the top and bottonrwith guideways 8, 3, (see 5 Figure 2) in which the restraining lips 4 and 5 on the blocks and straps are retained. The blocks are provided with cutter bits 6, 6. The cutter chain is made up of a series of chain blocks extending in various angles from the grooved cutter head 7 as shown in Figure 2. For the purpose of illustration (if my device, I have shown in detail one of such chain blocks having its cutter .bit centrally located thatis to say, perpendicular to the as "grooved cutter head, but it will be under: stood that the same features of construction are used in the other chain blocks having varying degrees of inclination to said cutter head. a

The cutter block is provided with a forsecton, for ease in manufacture.

Ward face 8 presenting a plane surface inintermediate its ends and is inclined forwardly and outwardly in its aperture 9 so that the forward face 10 of the bit emerges from the outer face 8 of the block immediately adjacent the outer edge of the forward face 8. The portion of the block extending beyond the grooved cutter head is preferably wider at the front end than at the rear, as shown in Figure 3. A shoulder 11 is formed to the rear of the aperture 9 to support the portion of the bit extending beyond the outer face 8*. The bit receiving aperture 9 extends downwardly and rearwardly between the holes 12, 12 which connect with the straps 2, 2. A suitable pin 13 extends through the lower end of the aperture 9 to limit the movement of the bit 6 so that it will not drop through the lower end of said aperture. Means for securing the bit comprises a clamping memberv 11, which fits into an aperture 15 opening to the rear end of the'block and extending forwardly therefrom substantially at right 7 angles to the bit 6, but closed at its forward end. Said clamp member comprises a body portion 16 having anaperture 17 intermediate its ends adapted to receive the cutter bit 6. Said body portion, and the aperture in which it fits, are preferably circular in cross The rear end of said clamping member is provided with a; threaded portion 18 extending beyond the rear face of the block, and adapted to receive a nut 19. Means are provided for preventing rotation of the clamping member which comprises a pin 20 extending through the block to engage a flattened surface 21 formed on the clamping member. The pin 20, when in place, is also adapted to engage a shoulder 22 to retain the clamping member in the block. A gripping piece of relatively hard material is provided in the forward wall of the aperture 17 in said clamping member to afford a firm and durable grip on the cutter bit 6. gripping piece preferably comprises a set screw 23 extending axiallythrough the'forward end of the clamping member 14.

, With a cutter chain constructed as above described, it will be seen thatthe front face 8 presents a plane surface unobstructed by set screws or similar clamping devices, and inclined to meet the front face of the cutter bit at a wide or obtuse angle. As the cutting proceeds, the cutter bit exerts a shearing action on the material to be cut and the cuttings are moved away from the cutting edge along the front face of the cutter bit and the unobstructed front face 8. Furthermore, the forward face 8 presents a plane surface toward the front of the block,

which tends to carry the cuttings out of the kerf, rather'than deflect the cuttings to opposite sides of the block.

The clamping member is arranged to engage the front face of the bit when placed under tension by the clamp 19, thereby holding said bit securely against the rear wall of the bit-receiving aperture in position to withstand the cutting stresses acting rearwardly 0a the bit. The clamping nut 19 is located in position for ready adjustment at the rear end of the cutter block, where it does not obstruct the front face, and is not subject to excessive wear. In connection with the cutter block, I am enabled to utilize an improved form of bit, comprising a double-end piece formed of straight, flat bar stock having a substantially uniform rectangular cross section intermediate its ends, and which is simple to manufacture,

readily heat-treated and ground, easily handled, and quickly adjusted in place in the chain block.

if claim as my invention:

1. A chain block having a bit receiving aperture inclined toward thefro'nt end of said block, a clamp-receiving aperture substantially at right angles to said bitreceiving aperture and closed to the front face of said block, a bit, a clamp having engagement with said bit, and a nut having threaded engagement with said clamp at the rear face of said block. 4

2. A chain block having a bit receiving aperture inclined toward the front end of said block, a clamp-receiving aperture substantially at right angles to said bit receiv: ing aperture and closed to the front face of said block, a bit, a clamp having engagement with said bit, a nut havmg threaded engagement with said clamp at the rear face of said block, and means preventing the rotation of said clamp with respect to the block.

3. In combination with avcutter blt, a chain block having an aperture adapted to receive said bit in a position inclined outwardly therefrom toward the front end of said block, and an unobstructed surface inclined forwardly and downwardly from,

and at an obtuse angle to, that portion of said bit projecting beyond said block, and clamping means adjustable from the rear end of the block for securing said bit in ing aperture and closed to the front face ofv said block, a bit, a clamp, a gripping device of relatively hard material mounted on said clamp adapted to engage the front surface of said bit, and a nut having threaded enagement with said clamp at the rear face of said block.

5. A chain block having a bit receiving aperture inclined toward the front end of said block, a clamp-receiving aperture substantially at right angles to said bit-receiving aperture and closed to the front face of said block, a bit having plane sides and substantially uniform in cross section intermediate its ends, a clamp having an aperture adapted to receive said bit, and a nut having threaded engagement with said clamp at the rear face of said block.

6. A chain block having a bit receiving aperture inclined toward the front end of said block, a clamp-receiving aperture substantially at right anglesto said bit-receiv in aperture, said clamp receiving aperture being closed to the front face and opening to the rear face of said block, a hit, a clamp I having engagement with said bit, a nuthaving threaded engagement with said clamp at the rear face of said block, and means independent of said bit for retaining said clamp in its aperture. Y

7. In a cutter chain, a chain block provided with a pair of laterally spaced holes adjacent its base adapted to heengaged by connecting links, said block having a bit re' ceiving aperture extending outwardly between said holes and inclined toward the front end of said block, a clamp-receiving aperture substantially at right angles to said bit receivin aperture and closed to the front face. 0 said block, a bit, a clamp having engagement with said bit, and a nut having threaded engagement with said clamp at the rear face of said block.

8. In a cutter chain, a chain block provided with a pair of laterally spaced holes adjacent its base adapted to be engaged by connecting links, said block having a bit receiving aperture extending outwardly be tween said holes and inclined toward --the front end of said block, and an unobstructed surface inclined forwardly and downwardly from the. forward edge of said aperture and at less than a right angle tosaid aperture, :1 bit in said aperture having a cutting edge toward the front end of the block, and obtuse angle therewith to permit a con clamping means adjustable from the rear tinuous downward movement of cuttings end of the block for securing said bit in from said bit to said face, and a rearwardly bearing engagement against the rear surface acting clamping device adjustable from the 0 of said bit-receiving aperture. rear end of said block for securing said bit in 15 9. A chain block having an unobstructed, said block.

inclined front face, a bit in said block hav- Signed at Chicago, Illinois, this 11th day ing a forward cutting face extending upof Dec. 1920. Wardly and forwardly from the upper edge 1 of said inclined front face and forming an THOMAS E. PRAY. 

